On Capitol Hill today, a truce in the budget wars. A dozen Republican senators agreed to let a bipartisan budget deal proceed to a final vote. That was the bill's last obstacle. It's expected to easily garner the 51 votes it needs for passage.

But as NPR's Ailsa Chang reports, the deal still has many critics in the Senate on both sides of the aisle.

AILSA CHANG, BYLINE: From the moment Democratic Senator Patty Murray and Republican Congressman Paul Ryan announced the deal, what you kept hearing over and over was the adjective modest. That was code for we didn't figure out the really hard issues, like how to cut Medicare and Social Security, and close tax loopholes.

Still, Saxby Chambliss of Georgia was one of the 12 Republican senators who helped the Democrats push the legislation through today.

SENATOR SAXBY CHAMBLISS: While this particular bill doesn't go nearly as far as I would like for it to go, relative to the $17 trillion debt, I think it's an important first step that needs to be voted on.

CHANG: Chambliss pointed out that at least the deal will slightly reduce the deficit by $23 billion over the next 10 years, and it will let Congress finally craft a spending plan before January 15th, when the government could have shut down again. Keeping the government open was key to getting another Republican on board, Ron Johnson of Wisconsin.

SENATOR RON JOHNSON: I didn't want to see the last shutdown. I do not want to be contemplating government shutdowns. We do enough harm to our economy through the federal government. We need - don't need to hop - heap on more harm, you know, by threatening these shutdowns and managing crisis to crisis.

CARRIE JOHNSON, BYLINE: But these yes votes were offset by plenty of griping. Many Republicans said it was a mistake to reverse the across-the-board spending cuts that were set for January. Others grumbled about how their negotiators had failed to achieve any cuts to mandatory spending programs like Social Security.

Here's Republican Bob Corker of Tennessee.

SENATOR BOB CORKER: I mean, it's the central issue of our day, the central issue of our day. And none of the things that we met with the White House and so many others about relative to mandatory issues made it into this bill. And in the Senate side, you know, we had no opportunity whatsoever to amend.

CHANG: And some of Corker's colleagues were livid that the bill extracted savings by paring down cost-of-living increases for military retirees under age 62. Roger Wicker of Mississippi said the government was breaking a promise to veterans.

SENATOR ROGER WICKER: It says to people who've completed their service, who've completed the full 20 years of their bargain, you may have done what we asked you to do, but now the government is not going to do what we told you we would do.

CHANG: Democrats chimed in as well with their own criticisms of the plan. Tom Harkin of Iowa voted to let the Senate move forward on the bill, but he says he still doesn't like the measure because it doesn't extend long-term jobless benefits set to expire December 28th.

SENATOR TOM HARKIN: What about all these people that are out of work and can't find a job? And we know the unemployment rate is extremely still high. We've never cut off unemployment compensation when a recession - unemployment's been this high. It's just, to me, unconscionable. So I'm just upset about that.

CHANG: Senate Majority Leader Harry Reid promised he'd take up legislation to extend unemployment benefits as soon as the Senate returns from its holiday break, but Harkin says by then, it may be too late.

HARKIN: We don't have a vehicle to get it through. This is the vehicle that would have gotten it through. That's a false promise to say we're going to take it up, because it'll never get through.